Jim Haydon inspected the RF cables and tightened down connections. He found and tightened a wobbly connection on a grounding strap to the upper electrode. The system etches now without flickering plasma. It tunes reasonably well for recipes 1 and 99. However, the tune and load settings are still near their limit.
The system is conditionally OK to use. It will be fine for zero level mark etching on blank silicon wafers. It may not tune well for other recipes or other wafers -- conditions where the automatch is at the limit. So please run test wafers for your recipe and watch your wafers very carefully. If the system faults for RF match, do not continue running your recipe or wafers.
We hope to try to find ways to recenter the match system on Monday.